Sergey Alexeyevich Chaplygin (russian: Серге́й Алексе́евич Чаплы́гин; 5 April 1869 – 8 October 1942) was a Russian and
Soviet
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate caus ...
, mathematician, and mechanical
engineer
Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the l ...
. He is known for mathematical formulas such as
Chaplygin's equation In gas dynamics, Chaplygin's equation, named after Sergei Alekseevich Chaplygin (1902), is a partial differential equation useful in the study of transonic flow. It is
:
\frac +
\frac\frac+v \frac=0.
Here, c=c(v) is the speed of sound, determi ...
and for a hypothetical substance in cosmology called
Chaplygin gas Chaplygin gas,
which occurs in certain theories of cosmology, is a hypothetical substance that satisfies an exotic equation of state in the form
p = -A/\rho^\alpha
,
where p is the pressure, \rho is the density, with \alpha = 1 and A a positive c ...
, named after him.
He graduated in 1890 from
Moscow University
M. V. Lomonosov Moscow State University (MSU; russian: Московский государственный университет имени М. В. Ломоносова) is a public research university in Moscow, Russia and the most prestigious ...
, and later became a professor. He taught mechanical engineering at
Moscow Higher Courses for Women in 1901, and of applied mathematics at Moscow School of Technology, 1903. He was appointed Director of the courses in 1905.
Leonid I. Sedov
Leonid Ivanovich Sedov (russian: Леонид Иванович Седов; 14 November 1907 – 5 September 1999) was a leading Soviet expert on hydro- and aerodynamics and applied mechanics.
In 1930 Sedov graduated from the Moscow State Universit ...
was one of his students.
Chaplygin's theories were greatly inspired by
N. Ye. Zhukovsky, who founded the
Central Institute of Aerodynamics. His early research consisted of hydromechanics. His "Collected Works" in four volumes were published in 1948.
Honours and awards
*
Hero of Socialist Labour
The Hero of Socialist Labour (russian: links=no, Герой Социалистического Труда, Geroy Sotsialisticheskogo Truda) was an honorific title in the Soviet Union and other Warsaw Pact countries from 1938 to 1991. It repre ...
(1 February 1941)
* Two
Orders of Lenin
The Order of Lenin (russian: Орден Ленина, Orden Lenina, ), named after the leader of the Russian October Revolution, was established by the Central Executive Committee on April 6, 1930. The order was the highest civilian decoration b ...
(1 February 1941 and 22 December 1933)
*
Order of the Red Banner of Labour
The Order of the Red Banner of Labour (russian: Орден Трудового Красного Знамени, translit=Orden Trudovogo Krasnogo Znameni) was an order of the Soviet Union established to honour great deeds and services to th ...
, twice (10 July 1927 and ?)
*
Zhukovsky Prize (1925)
Chaplygin was elected to the
Russian Academy of Sciences
The Russian Academy of Sciences (RAS; russian: Росси́йская акаде́мия нау́к (РАН) ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across t ...
(the Academy of Sciences of the USSR in 1925-1991) in 1924.
The lunar crater
Chaplygin and town
Chaplygin are named in his honour.
See also
*
Chaplygin gas Chaplygin gas,
which occurs in certain theories of cosmology, is a hypothetical substance that satisfies an exotic equation of state in the form
p = -A/\rho^\alpha
,
where p is the pressure, \rho is the density, with \alpha = 1 and A a positive c ...
*
Chaplygin problem
In mathematics, particularly in the fields of nonlinear dynamics and the calculus of variations, the Chaplygin problem is an isoperimetric problem with a differential constraint. Specifically, the problem is to determine what flight path an ai ...
*
Chaplygin's equation In gas dynamics, Chaplygin's equation, named after Sergei Alekseevich Chaplygin (1902), is a partial differential equation useful in the study of transonic flow. It is
:
\frac +
\frac\frac+v \frac=0.
Here, c=c(v) is the speed of sound, determi ...
*
Lamb–Chaplygin dipole
The Lamb–Chaplygin dipole model is a mathematical description for a particular inviscid and steady dipolar vortex flow. It is a non-trivial solution to the two-dimensional Euler equations. The model is named after Horace Lamb and Sergey Alexeyev ...
*
Chaplygin sleigh
The Chaplygin sleigh is a simple pedagogical example of a nonholonomic system in mechanics, described by Sergey Chaplygin
Sergey Alexeyevich Chaplygin (russian: Серге́й Алексе́евич Чаплы́гин; 5 April 1 ...
*
Chaplygin's top
In classical mechanics, the precession of a rigid body such as a spinning top under the influence of gravity is not, in general, an integrable problem. There are however three (or four) famous cases that are integrable, the Euler, the Lagrange, ...
External links
*
{{DEFAULTSORT:Chaplygin, Sergey Alexeyevich
1869 births
1942 deaths
People from Chaplygin
Mathematicians from the Russian Empire
Heroes of Socialist Labour
Recipients of the Order of Lenin
Full Members of the USSR Academy of Sciences
Corresponding Members of the Russian Academy of Sciences (1917–1925)
Moscow State University alumni
Physicists from the Russian Empire
Soviet mathematicians
Soviet physicists
19th-century mathematicians from the Russian Empire
20th-century Russian mathematicians
20th-century Russian physicists
Russian mechanical engineers
Soviet mechanical engineers
Engineers from the Russian Empire
Central Aerohydrodynamic Institute employees